ios 11 app store wont let me download apps. Help please

I log into my itunes/app store account in settings. When I open up the App Store and try to download an app, it tells me i have to sign in again. It then pops up with a log in page in the App Store. Then when i finish signing in the app doesn't download. So I again press download, it again asks for my password then shows the loading icon for a second then goes back to saying "get". If i go back into settings I am logged out of my Itunes account.

I am using an Ipad Air 2.

Does anyone else have this issue? and how should i go about fixing it?